JP5697509B2 - Interior materials for vehicles - Google Patents

Description

  The present invention relates to a vehicle interior material. More specifically, the present invention specifies the shape of the clip holder provided on the surface of the interior material base by the injection molding method, thereby generating warpage due to thermal contraction of the clip holder in the cooling process after molding. Further, the present invention relates to an interior material for a vehicle in which the generation of a dent in the design surface on the passenger compartment side due to heat during molding is suppressed.

  The vehicle interior material is provided with a holder such as a retainer and a side clip for attaching the interior material to the vehicle panel on a surface opposite to the vehicle compartment side. Conventionally, this holder has been bonded and fixed to the surface of the interior material with an adhesive or the like, but it requires an adhesive or the like, and requires considerable effort and time to apply the adhesive. I was trying. For this reason, a method has been proposed in which resin is directly injected onto the interior material surface to form a holder, and is bonded to the interior material surface and fixed.

  For example, a molded body is joined to a base body such as a fiber board by a thermoplastic resin material, and a joint portion has a linear portion extending on the joint surface of the base body, and a branch projecting from the linear portion onto the joint surface. A molded structure formed by a portion is known, and it is described that the molded body is bonded with a sufficient bonding force without deforming the base (see, for example, Patent Document 1). Furthermore, a molding method of a resin molded body is known, in which a molding die having a specific cavity is used to mold a resin molded body, and a part of the molten resin is led out and bonded to the molding object. It is described that the cavity internal pressure based on the pressure or the like can be reduced to prevent damage to the molding, plastic deformation, or the like (see, for example, Patent Document 2).

Japanese Patent Laid-Open No. 2006-212824 JP 2006-142746 A

  As described above, a method of directly injecting resin on the surface of the interior material and molding the holder, for example, the method described in Patent Documents 1 and 2, can simplify the process and Can be bonded with sufficient strength. However, in particular, in the case of interior materials that are multi-layered, such as a roof trim, and have a relatively low rigidity among various interior materials, the retainer and its periphery are retained by the heat shrinkage of the retainer during the cooling process after molding. May be warped on the molded surface side (see FIG. 7 which is a schematic cross-sectional view of a part of the vehicle interior material 101 that has warped).

  In addition, non-woven fabrics often used as a base material layer for interior materials are blended with thermally expandable microcapsules to reduce the weight of the interior materials. In this case, bubbles are generated by heat during injection molding. The formed resin melts and breaks, and a dent may be formed on the design surface on the passenger compartment side (a schematic diagram of a partial cross section of the interior material 102 for a vehicle in which the dent 1a is generated on the design surface. (See FIG. 9). Further, the nonwoven fabric usually contains a thermoplastic resin blended as a binder, but the resin melts due to the heat during molding and the binding structure is disturbed, which may cause dents in the design surface. is there.

  The present invention has been made in view of the above-described prior art, and by specifying the shape of the clip holding portion provided on the surface of the interior material base by the injection molding method, the clip in the cooling process after molding An object of the present invention is to provide an interior material for a vehicle in which generation of warpage due to heat shrinkage of a holding portion and generation of a dent in a design surface on the passenger compartment side due to heat during molding are suppressed.

The present invention is as follows.
1. A vehicle interior material provided with a base, and a clip holding portion for holding a clip, provided on the surface of the base,
The clip holding portion is formed on the surface of the base body by an injection molding method, and the clip holding portion is integrally formed with the seat portion joined to the surface of the base body, the seat portion, A fitting portion for fitting the clip,
The fitting portion is configured to protrude from the seat portion to the side away from the surface of the base, and the seat portion is formed by a plane orthogonal to the surface of the base body while avoiding the fitting portion. The section of the seat section when virtually cut is gradually thinned toward the end of the entire section of the seat section, and the line segment joined to the surface of the base body of the outer periphery of the section of the seat section Is shorter than the length obtained by subtracting the length of the line segment from the total length of the outer peripheral line.
2. The surface side of the base is made of a non-woven fabric, and the entire surface of the seat contacting the base is joined to the non-woven fabric. The vehicle interior material described in 1.
3. Of the outer peripheral lines of the seat section, the length of a line segment joined to the surface of the base is A, and the length obtained by subtracting the length of the line segment from the total length of the outer peripheral line is B. , A and B satisfy the following formula. Or 2. The vehicle interior material described in 1.
A × 1.005 <B <A × 1.025

In the vehicle interior material of the present invention, since the clip holding part having a specific shape is provided by injecting the resin raw material onto the surface of the base, the warp due to the thermal contraction of the clip holding part in the cooling process after molding. Is suppressed, and the warping of the interior material to the surface side where the clip holding portion is provided is suppressed. In addition, since the time required for cooling after molding can be shortened, the occurrence of dents on the design surface on the passenger compartment side can be suppressed. Furthermore, the time required for molding can be shortened as compared with a method in which a previously molded part is bonded to the surface of the substrate and fixed. Further, since the cooling time can be shortened, the molding cycle time can be shortened, and the productivity can be improved.
Moreover, the length of the line segment joined to the surface of the base in the outer peripheral line of the seat section is A, and the length obtained by subtracting the length of the line segment from the total length of the outer peripheral line is B. In this case, when A and B satisfy the above formula, the warpage to the surface side where the clip holding portion is provided and the generation of dents on the design surface on the passenger compartment side are sufficiently suppressed, and the productivity is further improved. To do.

It is a schematic diagram of a part of a cross section of a vehicle interior material provided with a clip holding portion in which the surface of a seat portion is an inclined surface. It is a typical perspective view of the clip holding | maintenance part of FIG. (A) is a cross section of the seat portion of the clip holding portion in which the surface of the seat portion becomes an inclined surface in order to suppress warpage (a cross section when virtually cut by the plane P including the broken line a in FIG. 2). FIG. (B) is a schematic diagram for explaining L1 and L2 in (A). FIG. 6 is a schematic cross-sectional view of a cross section of a seat portion of a clip holding portion in which the surface of the seat portion has a concave curved surface in order to suppress warping. FIG. 5 is a schematic cross-sectional view of a cross section of a seat portion of a clip holding portion in which the surface of the seat portion has a convex curved surface in order to suppress warping. It is a schematic diagram of a part of a cross section of a vehicle interior material provided with a clip holding part having a seat part of a conventional shape. It is a schematic diagram of a cross section of a part of the vehicle interior material that has warped to the surface side where the clip holding portion is provided due to thermal contraction of the clip holding portion. It is a schematic diagram of the cross section of the seat part of the conventional clip holding | maintenance part whose thickness is substantially the same in the length direction. Due to the heat generated when the clip holding part is molded, the resin forming the bubbles in the base material layer melts and breaks, and a part of the interior material for the vehicle has a dent in the design surface on the passenger compartment side. It is a schematic diagram of a cross section.

Hereinafter, the present invention will be described in detail with reference to the drawings.
The items shown here are for illustrative purposes and exemplary embodiments of the present invention, and are the most effective and easy-to-understand explanations of the principles and conceptual features of the present invention. It is stated for the purpose of providing what seems to be. In this respect, it is not intended to illustrate the structural details of the present invention beyond what is necessary for a fundamental understanding of the present invention. It will be clear to those skilled in the art how it is actually implemented.

The vehicle interior material 100 of the present invention includes a base body 1 and a clip holding portion 2 that is provided on the surface of the base body 1 and holds a clip (see FIG. 1). The clip holding portion 2 is formed on the surface of the base body 1 by an injection molding method. The clip holding portion 2 has a seat portion 21 joined to the surface of the base body 1 (surface on the vehicle panel side), and a seat portion 21. And a fitting portion 22 for fitting a clip. The fitting portion 22 is configured to protrude to the side away from the surface of the base body 1 with respect to the seat portion 21 (see FIG. 1), and the seat portion 21 is orthogonal to the surface of the base body 1 while avoiding the fitting portion 22. The entire cross-section of the seat portion when virtually cut by the flat surface is gradually thinner toward the end (see FIGS. 1 to 5). Thereby, the length of the line segment joined to the surface of the base 1 in the outer peripheral line of the seat section becomes shorter than the length obtained by subtracting the length of the line segment from the total length of the outer peripheral line.

  The base body 1 of the vehicle interior material 100 has a surface on the vehicle panel side and a surface on the vehicle compartment side when attached to the vehicle, and the clip holding portion 2 is on the surface on the vehicle panel side. Provided (see FIG. 1). And one end side of a clip is hold | maintained at the clip holding | maintenance part 2, the other end side of a clip is attached to the attachment hole etc. which were provided in the vehicle panel, and the vehicle interior material 100 is fixed to a vehicle panel.

[1] Clip Holding Part The “clip holding part 2” is integrally formed with the “seat part 21” joined to the surface of the base body 1 of the vehicle interior material 100 and the seat part 21, and is used for fitting a clip. The “fitting portion 22” is provided (see FIGS. 1 and 2). Moreover, the fitting part 22 is formed in the form protruded in the side spaced apart from the surface of the base | substrate 1 rather than the seat part 21 (refer FIG. 1).

  The clip holding part 2 is formed on the surface of the base body 1 by an injection molding method using a resin raw material. That is, the resin raw material is directly injected onto the surface of the base 1 and cooled to form the clip holding part 2. In such a method, a resin material is usually injected into a cavity provided between the injection molding machine and the substrate surface from an injection molding machine whose movement in the three-dimensional direction is controlled, and a predetermined location on the substrate surface is obtained. The required number of clip holders 2 are continuously formed.

In the present invention, the seat portion 21 of the clip holding portion 2 is disposed on a plane orthogonal to the surface S (see FIG. 1) of the base 1 while avoiding the fitting portion 22 [for example, an imaginary line (two-dot chain line a) in FIG. The entire section of the seat section when it is virtually cut according to the plane P included] gradually becomes thinner toward the end, and the line segment joined to the surface of the base body 1 of the outer peripheral lines of the section of the seat section. The length L1 is shorter than the length L2 obtained by subtracting the length of this line segment from the total length of the outer peripheral line [FIG. 3B is a diagram for explaining L1 and L2, and the solid line represents L1. The broken line represents L2. ].

The above-mentioned “cutting while avoiding the fitting portion 22” means that when the seat portion 21 is virtually cut, the plane P perpendicular to the surface S of the base body 1 is a boundary line between the seat portion 21 and the fitting portion 22. This means that the seat portion 21 is cut in a direction perpendicular to the surface of the base body 1 in contact with or outside the boundary line. The position of this cutting is not particularly limited as long as the fitting portion 22 is avoided, but it is preferable that the plane P is a position in contact with the boundary line between the seat portion 21 and the fitting portion 22. ,
(1) When the planar shape of the seat part 21 is a rectangle, the virtual part (refer to the dashed-two dotted line a of FIG. 2) which touches the boundary line of the seat part 21 and the fitting part 22 and is parallel to a long side is included. Cut by plane P (see plane P in FIG. 2).
(2) When the planar shape of the seat portion 21 is a square, the seat portion 21 is cut by a plane P that is in contact with the boundary line between the seat portion 21 and the fitting portion 22 and includes a virtual line a parallel to one side.
(3) When the planar shape of the seat part 21 is an ellipse, it cut | disconnects by the plane P which contact | connects the boundary line of the seat part 21 and the fitting part 22, and contains the virtual line a parallel to a major axis.
(4) When the planar shape of the seat portion 21 is circular, the plane P includes a virtual line a that is in contact with the boundary line between the seat portion 21 and the fitting portion 22 and has the longest radial length of the cut surface. Cut with.
(5) When the planar shape of the seat portion 21 is a shape other than the above (1) to (4), it is in contact with the boundary line between the seat portion 21 and the fitting portion 22 and the width direction of the cut surface (the seat portion 21). It is assumed that cutting is performed by the plane P including the virtual line a having the longest length in the direction perpendicular to the thickness direction of the first layer.
In the present invention, the seat section is assumed to be a section when the seat section 21 is virtually cut as described in (1) to (5) above.

The “seat section cross section” when the seat section 21 is virtually cut is a form in which the entire section of the seat section becomes gradually thinner toward the end (see C1 in FIG. 3). The cross section of the seat portion is a form in which the entire cross section of the seat portion gradually becomes thinner toward the end from the viewpoint of simplifying the structure of the molding die and ease of molding . For example, it can be set as the clip holding | maintenance part 2 by which the surface of the seat part 21 became the inclined surface (refer FIG. 1 thru | or 3). Alternatively, the clip holding portion 2 may have a concave curved surface R1 on the surface of the seat portion 21 (see FIG. 4). The clip holding portion may have a convex curved surface R2 on the surface of the seat portion 21 (see FIG. 5). 2 can also be used.

As described above, since the entire cross section of the seat portion becomes gradually thinner toward the end, the length L1 of the line segment joined to the surface of the base body 1 in the outer peripheral line of the cross section of the seat portion is as follows. The length L1 is shorter than the length L2 obtained by subtracting the length L1 of the line segment from the total length of the outer peripheral line. In other words, of the outer peripheral line of the seat section, the surface opposite to the surface joined to the surface of the base body 1, that is, the length L2 on the surface side of the seat section is joined to the surface of the base body 1. It becomes longer than the length L1 of the line segment. With such a configuration, after the clip holding portion 2 is molded, the surface side of the seat portion 21 that can be freely shrunk in the cooling process is shrunk and joined to the surface of the base 1, and the joint surface side that cannot be freely shrunk is almost Even if it does not shrink, the clip holding part 2 is warped to the surface side, thereby suppressing the entire interior material at the periphery of the clip holding part 2 from being warped.

  The correlation between the length L1 of the line segment bonded to the surface of the base body 1 and the length L2 on the surface side of the seat section is a line on the surface side of the seat section. The length of the line segment joined to the surface of the substrate 1 is A (corresponding to L1), and the length obtained by subtracting A from the total length of the outer peripheral line is equivalent to B (L2). ), A and B preferably satisfy the above formula (A × 1.005 <B <A × 1.025). The correlation between A and B is preferably set based on the shrinkage rate determined by the shape and size of the clip holding unit 2 and the type of resin used for molding, etc. [For example, the clip holding unit in Comparative Example 1 described later] In the case of 2, the dimension in the long side direction of the seat part 2 after cooling contracts by 15/1000 of the dimension of the seat part 2 before cooling. Therefore, if A = 1.015B, warping after cooling can be substantially prevented. ]. If the correlation between A and B is set in this way, the warp of the clip holding unit 2 and the inner periphery of the clip holding unit 2 due to the warp are independent of the shape, size, material, etc. of the clip holding unit 2. Warpage of the entire material can be sufficiently suppressed.

In addition, if the entire section of the seat section becomes gradually thinner toward the end, for example, the clip holding section 2 having the section of the seat section as shown in FIGS. The heat capacity of the clip holding unit 2 can be reduced as compared with the case where the length is substantially the same (see FIG. 8). Therefore, the temperature can be lowered more quickly after formation, and the amount of heat transmitted to the base material layer 11 can be reduced. As a result, it is possible to sufficiently suppress the occurrence of a dent (see the dent 1a in FIG. 9) on the design surface on the passenger compartment side.

  The resin raw material used for molding the clip holding part 2 is not particularly limited, and various thermoplastic resins can be used. The thermoplastic resin is not particularly limited. Polyolefin resins such as polypropylene and high-density polyethylene, polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, polyamide resins such as nylon 6 and nylon 66, polymethyl Various thermoplastic resins such as polyacrylic resins such as methacrylate are exemplified. As the thermoplastic resin, a polyolefin-based resin that can be easily formed by injection molding and has a sufficient strength and the like, particularly a polypropylene-based resin such as a propylene homopolymer and an ethylene / propylene block copolymer Is preferred. The thermoplastic resin usually contains various antioxidants, UV absorbers, lubricants, antistatic agents, pigments, fillers, flame retardants, flame retardant aids, and the like. These other components may be used alone or in combination of two or more.

[2] Substrate The “base 1” is the skin layer 12 that forms the design surface on the side of the passenger compartment, the base material layer 11, the skin layer 12 and the base material layer for maintaining the shape of the interior material and imparting strength. 11 and an adhesive film layer 13 having air permeability and functioning as a sound absorbing layer. Further, the air-proofing film is usually laminated on the surface of the base material layer 11 opposite to the skin layer 12 to prevent air and prevent dust and the like from adhering to the surface of the skin layer 12 that is the design surface. The non-woven fabric layer 15 is laminated on the surface opposite to the base material layer 11 of the layer 14 and the air blocking film layer 14 to facilitate handling during heating, pressure molding, etc. of the substrate 1 (see FIG. 1). ).

  The skin layer 12 can be formed using various woven fabrics, leathers, knitted fabrics, nonwoven fabrics, thermoplastic elastomer sheets, vinyl chloride leathers, and the like. Although the thickness of this skin layer 12 is not specifically limited, For example, it can be set as 0.5-3.0 mm, especially about 1.0-2.0 mm. In addition, the vehicle interior material 100 is usually arranged so that the skin layer 12 faces the vehicle compartment side, and the outer surface of the skin layer 12 becomes the design surface of the vehicle interior material 100.

The base material layer 11 is a layer that supports other layers such as the skin layer 12, and the vehicle interior material 100 has sufficient strength, buffering property, and the like by the base material layer 11. The base material layer 11 only needs to have sufficient rigidity to support the entire vehicle interior material, and the material is not particularly limited. For the formation of the base material layer 11, moldability, physical properties, etc. In view of the above, a nonwoven fabric or a resin foam is often used. The thickness of the base material layer 11 is not particularly limited, but may be 1.0 to 7.0 mm, particularly 2.0 to 4.0 mm, and further 2.0 to 3.0 mm. When the thickness is 1.0 to 7.0 mm, particularly 2.0 to 3.0 mm, the base material layer 11 can sufficiently support other layers such as the skin layer 12. Although not particularly limited weight per unit area of the base material layer 11, 200 to 800 g / ^{m 2,} in particular 300 to 600 g / ^{m 2,} can be further and 400-600 g / ^{m 2.} If the basis weight of the base material layer 11 is 200 to 800 g / m ² , particularly 400 to 600 g / m ² , the vehicle interior material 100 can have a sufficient strength and can be light.

When the base material layer 11 is made of a nonwoven fabric, the nonwoven fabric is not particularly limited. For example, the nonwoven fabric has inorganic fibers and / or natural fibers and a thermoplastic resin that binds at least a part of the entanglement points of these fibers. Can be used.
Examples of the inorganic fiber include glass fiber, carbon fiber, and metal fiber. Of these, glass fibers and / or carbon fibers are preferred. Only one type of inorganic fiber may be used, or two or more types may be used. Examples of natural fibers include plant fibers such as kenaf, hemp, cotton, palm fiber, and here palm fibers, and animal fibers such as silk and wool. Of these, hemp is preferred. Only one type of natural fiber may be used, or two or more types may be used. Furthermore, inorganic fibers and natural fibers can be used in combination. These inorganic fibers and natural fibers are usually fibrillated long fibers.

  The thermoplastic resin is mixed with inorganic fibers and / or natural fibers in the form of fibers, powders, etc., and melts when the formed web is heated and pressurized, and the molten thermoplastic resin allows the inorganic fibers and / or Or the entanglement point of a natural fiber is bound. This thermoplastic resin is not particularly limited, and polyolefin resins such as polypropylene and polyethylene; acrylic resins such as polymethyl acrylate and polymethyl methacrylate; polyamide resins such as nylon-6 and nylon-66; and polyethylene terephthalate Examples thereof include polyester resins. Of these, polyolefin resins, particularly polypropylene resins such as polypropylene homopolymers are preferred. Only one type of thermoplastic resin may be used, or two or more types may be used in combination. In this thermoplastic resin, additives usually used for this type of resin such as an antioxidant, an ultraviolet absorber, a lubricant, and an antistatic agent can be blended as required.

  Thermally expandable microcapsules can be blended in the nonwoven fabric to be the base material layer 11. In this case, the vehicle interior material 100 can be made lighter by expanding the thermally expandable microcapsules during heating and pressurization in the molding process of the base body 1 of the vehicle interior material 100. Thermally expandable microcapsules usually contain volatile hydrocarbons such as butane and isobutane in the outer shell, and the outer shell contains vinylidene chloride-acrylonitrile copolymer, polyvinyl chloride, polyvinylidene chloride, polyacrylic. It is composed of nitrile or the like.

  The heat-expandable microcapsule is generally spherical with a diameter of 10 to 100 μm, particularly about 20 to 80 μm, and expands 4 to 30 times by heating to a temperature range exceeding the thermal expansion start temperature. The diameter after the body expansion depends on the diameter before the body expansion and the expansion ratio, but is, for example, 40 to 600 μm, particularly 60 to 400 μm. By using such a heat-expandable microcapsule, the base material layer 11 can be reduced in weight, and since it has a porous structure, the vehicle interior material 100 having sufficient sound absorption and the like can be obtained. .

The base material layer 11 can also be formed of a resin foam, particularly a polyurethane foam. The polyurethane foam layer used as the base material layer 11 uses foam raw materials containing polyol, polyisocyanate, crosslinking agent, catalyst, foaming agent, foam stabilizer, etc., foamed by a conventional method, and has a predetermined dimension from the molded slab foam. It can produce by methods, such as cutting out so that it may become. In addition to the various components described above, various additives such as antioxidants, ultraviolet absorbers, fillers, internal mold release agents, flame retardants and the like can be blended in the foam raw material as necessary. .
In addition, the polyurethane foam used for the base material layer 11 is thermosetting, and a dent does not usually arise on the surface of the base body 1 by heat at the time of forming the clip holding part 2.

  Furthermore, in this base | substrate 1, the air-permeable prevention film layer 14 can be provided in the surface on the opposite side to the surface where the skin layer 12 of the base material layer 11 is joined (refer FIG. 1). Although this air-blocking film layer 14 is not particularly limited, films made of various synthetic resins such as polyolefin resins such as polypropylene, polyamide resins, polyester resins, and laminated films, for example, polyolefin resin films and polyamide resins It can be formed by a laminated film with a film. Thereby, the ventilation | gas_flowing over the thickness direction of the vehicle interior material 100 is interrupted | blocked or at least suppressed, the dust etc. which adhere to the surface of the skin layer 12 are reduced, and the more excellent design property is maintained. The interior material 100 can be used.

  Moreover, the nonwoven fabric layer 15 can also be provided in the surface on the opposite side to the surface joined to the base material layer 11 of the ventilation film layer 14 (refer FIG. 1). Although this nonwoven fabric layer 15 is not particularly limited, a thermoplastic resin fiber or powder is blended with inorganic fiber, natural fiber, etc., mixed by needling, etc., heated, pressurized, and entangled with inorganic fiber, natural fiber, etc. Can be formed using a general nonwoven fabric such as a nonwoven fabric bound by a thermoplastic resin. Thereby, it can be set as the base | substrate 1 which is easy to handle at the time of heat-press molding of the base | substrate 1, etc., and when providing the clip holding | maintenance part 2, etc., and workability | operativity can be improved.

  The manufacturing method of the vehicle interior material 100 of the present invention is not particularly limited, and can be manufactured by a normal method such as a vacuum forming method. As this vacuum forming method, for example, a base material (for example, a fiber board made of a heat-compressed nonwoven fabric, which becomes the base material layer 11) preliminarily formed into a desired shape is heated. And a method of laminating a multilayer sheet of an outer skin material (becomes an outer skin layer 12) and an adhesive film (becomes an adhesive film layer 14) simultaneously with vacuum forming.

  Further, the vacuum forming method includes a convex drawing vacuum forming method, a concave drawing vacuum forming method, a vacuum forming method using both of these methods, a method of forming by means of plug assist etc. simultaneously with the convex drawing vacuum forming, and upper and lower molds. Various methods such as a vacuum forming method in which vacuuming is performed simultaneously with pressing with a mold are included. Moreover, it can also be vacuum-formed using the preformed sheet | seat which laminated | stacked the ventilation stopper film and the nonwoven fabric previously on the fiber board etc. which become the base material layer 11 previously. Thereby, in addition to each above-mentioned layer, the interior material 100 for vehicles which has the ventilation film film layer 14 and the nonwoven fabric layer 15 together can be manufactured.

Hereinafter, the present invention will be specifically described with reference to examples (see FIGS. 1 to 3 and 6 to 9).
Example 1
Polypropylene (manufactured by Prime Polymer Co., Ltd., trade name) is applied to a predetermined portion of the surface of the nonwoven fabric layer 15 of the substrate 1 having a thickness of 5.0 mm manufactured by a conventional method using an injection molding machine in which movement in a three-dimensional direction is controlled. “LA880”) was sequentially injected at a temperature of 200 ° C. (set temperature of the cylinder of the molding machine). Then, it was naturally cooled and the temperature was lowered to room temperature (25 to 30 ° C.), the clip holding part 2 was formed on the surface of the base 1, and the vehicle interior material 100 was manufactured. The planar shape of the clip holding part 2 is a rectangle, the seat part 21 has a long side of 66 mm and a short side of 22 mm, and the plane dimension in the long side direction is 18.5 mm at the center of one long side. A fitting portion 22 having a substantially circular shape is provided (see FIG. 2). Further, the cross section of the seat portion (the cross section when virtually cut by the plane P including the two-dot chain line a in FIG. 2) is directed from the boundary portion with the fitting portion 22 toward the end as shown in FIG. It has an inclined surface that becomes gradually thinner, and the thickness at the boundary is 2 mm.

Comparative Example 1
A vehicle interior material 100 was manufactured in the same manner as in Example 1 except that the clip holding portion 2 having the seat portion 21 having the conventional shape shown in FIG. The planar shape of the clip holding part 2 is the same as that of the first embodiment, but the thickness of the seat part 21 is the whole from the boundary part to the end of the seat part 21 and the fitting part 22 as shown in FIGS. It is about 2 mm and is substantially the same thickness.

[1] Evaluation of vehicle interior material The degree of warpage and dent after cooling during injection molding was evaluated.
(1) Warpage Warpage is such that the side where the planar shape peeled from the base body 1 is the joint surface with the base body of the rectangular clip holding part 2 is in contact with the center part in the long side direction on the plane, and Evaluation was made based on the distance between the bottom surface and the flat surface at both ends in the long side direction when the bottom surface and the flat surface at both ends in the long side direction were placed at an equal distance.
(2) Recess A recess is a skin that is a design surface on the vehicle compartment side when the vehicle interior material 100 is cut in the cross-sectional direction at the position where the clip holding portion 2 is provided and the cut surface is observed with an optical microscope. Evaluation was made based on the maximum depth of the recesses formed on the layer 12 side.

[2] Evaluation Results As a result of the evaluation as described above, the warpage was about 2.0 mm or less in Comparative Example 1 whereas it was 0.5 mm or less in Example 1 (4 in the same manner as in Example 1). When the vehicle interior material 100 was manufactured, the warpage was 0.5 mm at the maximum and 0.0 mm at the minimum. Thus, it turns out that curvature is reduced significantly by making a seat part into a specific shape. This is because the clip holding portion does not deform even when the surface side of the clip holding portion contracts. Further, the dents were 0.1 to 0.3 mm in Comparative Example 1 (when four vehicle interior materials 100 were manufactured in the same manner as in Comparative Example 1, the dents were 0.3 mm at the maximum and 0.1 mm at the minimum. In contrast, in Example 1, substantially no dent was observed. This is presumed to be due to the decrease in the volume of the clip holding portion, which quickly cools down after molding and reduces the amount of heat transmitted to the inside of the substrate.
still,

  The vehicle interior material of the present invention can be used in the technical field of various vehicle interior materials. Examples of the vehicle interior material include a roof trim, a floor trim, and a door trim. The vehicle interior material of the present invention is particularly a relatively large molded product, and is useful in the technical field of roof trim having a lower rigidity than other interior materials.

  DESCRIPTION OF SYMBOLS 100; Interior material for vehicles, 101; Interior material for vehicles warped centering on clip holding | maintenance part, 102; Interior material for vehicles in which the design surface by the side of a compartment produced the dent, 1; Base | substrate, 11; Layer, 12; skin layer, 13; adhesive film layer, 14; air-permeable film layer, 15; nonwoven fabric layer, 1a; dent generated in the design surface on the passenger compartment side; 2; clip holding portion; 22; fitting part.

Claims (3)

A substrate;
A vehicle interior material provided on the surface of the base body and provided with a clip holding portion for holding a clip,
The clip holding part is formed on the surface of the base by an injection molding method,
In the clip holding part,
A seat joined to the surface of the substrate;
A fitting portion that is integrally formed with the seat portion and for fitting the clip;
The fitting portion is configured to protrude from the seat portion to the side away from the surface of the base body,
The seat section is gradually thinner as it goes to the end when the seat section is virtually cut by a plane perpendicular to the surface of the base while avoiding the fitting portion,
Of the outer peripheral lines of the seat section, the length of the line segment joined to the surface of the substrate is shorter than the total length of the outer peripheral line minus the length of the line segment. Characteristic interior material for vehicles. The vehicle interior material according to claim 1, wherein the surface side of the base is made of a non-woven fabric, and the entire surface of the seat that contacts the base is bonded to the non-woven fabric. Of the outer peripheral lines of the seat section, the length of a line segment joined to the surface of the base is A, and the length obtained by subtracting the length of the line segment from the total length of the outer peripheral line is B. The vehicle interior material according to claim 1 or 2 , wherein A and B satisfy the following formula.
A × 1.005 <B <A × 1.025

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